/* Copyright 2024 The OpenXLA Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

#ifndef XLA_HLO_TRANSFORMS_SIMPLIFIERS_REDUCE_WINDOW_RESIZER_H_
#define XLA_HLO_TRANSFORMS_SIMPLIFIERS_REDUCE_WINDOW_RESIZER_H_

#include "absl/container/flat_hash_set.h"
#include "absl/status/statusor.h"
#include "absl/strings/string_view.h"
#include "xla/hlo/ir/hlo_module.h"
#include "xla/hlo/pass/hlo_pass_interface.h"

namespace xla {

// Rewrites 1D reduce-windows and reshape them to 2D reduce-windows. This helps
// for better tiling and avoids overly large reductions complexities and
// restrictions therein.
class ReduceWindowResizer : public HloModulePass {
 public:
  ReduceWindowResizer() = default;

  absl::string_view name() const override { return "reduce-window-resizer"; }

  absl::StatusOr<bool> Run(
      HloModule* module,
      const absl::flat_hash_set<absl::string_view>& execution_threads) override;
};

}  // namespace xla

#endif  // XLA_HLO_TRANSFORMS_SIMPLIFIERS_REDUCE_WINDOW_RESIZER_H_
